A dynamic stress analysis system and method for assembled beam string structure

Abstract

The present invention proposes a dynamic stress analysis system and method for a prefabricated beam string structure, which realizes comprehensive monitoring of structural strain, vibration, displacement, temperature, soil pressure and construction load by integrating multiple sensors, ensures data security through encrypted transmission, and adopts a role-based access control mechanism to protect sensitive data. During the data processing, key vibration characteristics are extracted by cleaning, calibrating and synchronizing data, and the temperature influence is considered. Finite element analysis is used to simulate the structural response, and a stress prediction model is established to identify potential damage areas and predict the remaining service life of the structure, thereby facilitating timely maintenance measures, ensuring structural safety, and improving the efficiency and accuracy of health management of prefabricated beam string structures.

Description

Technical Field

[0001] The present invention relates to the technical field of building foundation pit construction monitoring, and in particular to a system and method for dynamic stress analysis of an assembled beam-string structure. Background Art

[0002] Prefabricated beam-string structures have been widely used in the field of modern construction due to their high efficiency and fast construction. However, such structures are exposed to various external loads during use, such as wind loads, seismic loads, temperature changes, etc. These loads may cause dynamic stress in the structure, thus affecting its long-term safety and durability. Therefore, it is very important to conduct dynamic stress analysis and health monitoring of prefabricated beam-string structures.

[0003] Existing monitoring systems often rely on traditional sensor technologies, which may not provide high enough accuracy to monitor subtle strain changes or rapid vibration characteristics. In addition, the density and location of sensor deployment are often not sufficient to fully capture the behavior of the entire structure.

[0004] Traditional analysis methods may not fully consider the impact of temperature changes on material properties, or fail to reasonably simulate the nonlinear behavior of structures under complex loads. Existing damage identification technologies may not be able to detect early signs of structural damage in a timely and accurate manner, which limits the effective prediction of the remaining service life of the structure. In addition, due to the lack of accurate models, existing prediction methods may not be able to accurately estimate the remaining usable time of the structure under specific conditions. Summary of the invention

[0005] The purpose of the present invention is to provide a system and method for dynamic stress analysis of an assembled beam string structure.

[0006] The problem to be solved by the present invention is to solve the problem of dynamic stress monitoring and health assessment of prefabricated beam string structures, integrate multiple sensors for real-time monitoring, and use advanced data processing and analysis techniques to establish a stress prediction model to identify potential damage areas and predict the remaining service life of the structure, thereby ensuring structural safety and guiding maintenance decisions.

[0007] A method for dynamic stress analysis of an assembled beam string structure, the technical solution adopted is as follows:

[0008] S1: Install high-precision strain gauges to monitor strain changes at key parts of the structure, deploy multi-point accelerometers at different parts of the structure to monitor vibration characteristics, identify vibration frequency and amplitude, use linear displacement sensors to measure displacement changes at different locations of the structure, deploy temperature sensors to monitor temperature changes in various parts of the structure, install earth pressure gauges to measure changes in soil pressure on the structure, install construction load sensors on construction equipment to monitor changes in construction loads, and deploy axial force sensors to monitor changes in the supporting axial forces of the beam string structure supports and connection nodes;

[0009] S2: Combine wired and wireless communication technologies to transmit the collected data, encrypt the data in transmission, assign different priorities to different types of data, add CRC codes to the data packets to detect errors during transmission, and use FEC error correction coding technology to automatically repair errors in data transmission at the receiving end;

[0010] S3: Use a role-based access control mechanism to grant authorized users access to sensitive data;

[0011] S4: Clean the data, remove invalid and erroneous data points, calibrate the sensor data, synchronize and unify the data of different sensors in time, use FFT to analyze the vibration signal, extract the vibration frequency and amplitude of the beam string structure, consider the effect of temperature change on material properties, adjust the strain and displacement data, combine nonlinear material properties and geometric nonlinearity, simulate the behavior of the structure under complex loads, and use soil mechanics theory to evaluate the force of the foundation on the structure;

[0012] S5: Combine the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and support axial force to establish a stress prediction model to predict the dynamic stress response of the structure;

[0013] S6: Identify potential damage areas by comparing the dynamic stress prediction results with the maximum stress allowed by the design, and predict the remaining service life of the structure based on the damage identification results;

[0014] S7: Set warning thresholds according to structural design standards. When monitoring data exceeds the threshold, an alarm is triggered immediately, and notifications are sent to relevant personnel to remind them to take action. Results based on data analysis are provided to assist engineers and managers in making timely and effective maintenance decisions.

[0015] S8: Develop a user-friendly interface to display monitoring data and analysis results in a graphical manner and automatically generate regular monitoring reports summarizing the structural conditions and recommended measures.

[0016] Furthermore, the S1 installs a high-precision strain gauge, deploys multi-point accelerometers at different parts of the structure, uses a linear displacement sensor, arranges a temperature sensor, installs an earth pressure gauge, installs a construction load sensor on the construction equipment, and arranges an axial force sensor, including:

[0017] The strain gauge is set with a monitoring frequency of 5Hz and a data recording interval of 1 second. It is installed at the stress-bearing parts and connection nodes of the beam string structure. The accelerometer is set with a monitoring frequency of 50Hz and a data recording interval of 1 second. It is installed at the top, middle and bottom of the beam string structure. The displacement sensor is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 seconds. It is installed at the key support points and free ends of the beam string structure. The temperature sensor is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 minutes. It is installed at various key components and joints of the beam string structure. The soil pressure gauge is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 minutes. It is installed in the soil around the foundation pit. The construction load sensor is set with a monitoring frequency of 5Hz and a data recording interval of 1 second. It is installed on the hook of the crane. The axial force sensor is set with a monitoring frequency of 1Hz and a data recording interval of 1 second. It is installed at the supports and connection nodes of the beam string structure.

[0018] Furthermore, in S2, different priorities are assigned to different types of data, CRC codes are added to data packets to detect errors during transmission, and FEC error correction coding technology is used to automatically repair errors in data transmission at the receiving end, including:

[0019] S21: classify strain data, frequency and amplitude data, and displacement data as high priority data, classify temperature data and soil pressure data as medium priority data, and classify construction load data as low priority data. Control the sending order of data packets at the transmission layer, set queues of different priorities at the data transmission layer, and send high priority data first.

[0020] S22: Select CRC-32 generator polynomial. At the sending end, perform CRC calculation on each data packet and append the CRC value to the end of the data packet. At the receiving end, recalculate the CRC value and compare it with the received CRC value. If the two CRC values ​​do not match, it indicates that an error has occurred in the data packet transmission process.

[0021] S23: At the transmitting end, redundant information is added to each data packet, LDPC coding is selected to encode the data packet, and an additional redundant data packet is generated. At the receiving end, the generated redundant data packet is used to resolve the lost data packet and restore the original data.

[0022] Furthermore, the S3 adopts a role-based access control mechanism, including:

[0023] S31: Data viewing permission is to view real-time data and historical data, data modification permission is to modify data records, including correcting erroneous data, data deletion permission is to delete invalid and outdated data records, data export permission is to export data for further analysis, device management permission is to configure and manage data acquisition devices, user management permission is to create new users, assign roles and permissions, and system configuration permission is to change system configuration, including alarm thresholds;

[0024] S32: Grant all permissions to the project administrator; grant data engineers data viewing permissions, data modification permissions, and equipment management permissions; grant structural engineers data viewing permissions and data export permissions; grant field technicians data viewing permissions and equipment management permissions; grant quality control personnel data viewing permissions and data modification permissions; and grant report writers data viewing permissions and data export permissions.

[0025] Furthermore, the S4 cleans the data, synchronizes and unifies the data of different sensors in time, extracts the vibration frequency and amplitude of the beam string structure, adjusts the strain and displacement data, simulates the behavior of the structure under complex loads, and evaluates the force of the foundation on the structure, including:

[0026] S41: Setting thresholds, identifying and removing data points that are beyond the normal range, and using interpolation to fill in missing and abnormal data points;

[0027] S42: Synchronize the timestamps of all sensors and data acquisition devices, and align the data of different sensors through the timestamps;

[0028] S43: Obtain the modal parameters of the structure, including the natural frequency, damping ratio and vibration mode, use fast Fourier transform (FFT) to analyze the vibration signal, and extract the vibration frequency and amplitude of the beam string structure itself;

[0029] S44: Combined with the influence of temperature change on the elastic modulus and Poisson's ratio of the material, the readings of the strain gauge and the displacement sensor are adjusted according to the temperature change, and the temperature coefficients of the strain gauge and the displacement sensor are obtained, that is, the rate of change of the sensor output when the temperature changes. The data of the strain gauge and the displacement sensor are adjusted according to the temperature coefficient. The adjusted strain value = the original strain value + (strain gauge temperature coefficient × (current temperature − reference temperature)), and the adjusted displacement value = the original displacement value + (displacement sensor temperature coefficient × (current temperature − reference temperature));

[0030] S45: Use finite element software ABAQUS to simulate the dynamic response of the structure under complex loads, consider nonlinear material properties and geometric nonlinearity, perform nonlinear dynamic analysis of the structure, select the time step according to the load characteristics and structural characteristics, and output the dynamic response of the structure under complex loads;

[0031] S46: The data measured by the earth pressure gauge is used in combination with soil mechanics theory and the finite element method to evaluate the pressure distribution of the soil on the structure. The finite element software ABAQUS is used to establish a three-dimensional model including the soil and the structure to analyze the changes in soil pressure over time and construction progress.

[0032] Furthermore, in S5, the stress prediction model is established by combining the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and supporting axial force, including:

[0033] S51: Select features from strain, vibration, displacement, temperature, pressure, construction load data and support axial force, and select strain mean, vibration frequency, amplitude peak, displacement mean, temperature change, pressure mean, construction load mean, and support axial force mean;

[0034] S52: extracting the acceleration change rate from the accelerometer data, extracting the strain gradient from the strain gauge data, extracting the temperature gradient from the temperature sensor data, and extracting the change rate of the construction load from the sensor data on the construction equipment;

[0035] S53: Divide the data set into a training set, a validation set, and a test set, standardize the features extracted in S51 and S52, use the training data set to train the model, use the validation data set to verify the prediction ability of the model, calculate the error between the predicted value and the actual value, and verify the effect of model fusion;

[0036] S54: The stress prediction model is obtained as follows: ,in is the total stress of the structure, is the elastic modulus of the structural material at room temperature, is the temperature coefficient of the structural material, is the temperature change, For strain, is the construction load, is the structural cross-sectional area, is the pressure of soil on the structure, is the vibration effect coefficient related to the structural characteristics, is the amplitude of vibration, is the vibration frequency, is the displacement of the structure, is the displacement gradient, To support the axial force, real-time strain, vibration, displacement, temperature, pressure and construction load data are used as input to obtain the real-time stress value of the structure.

[0037] Furthermore, the remaining service life of the structure is predicted based on the damage identification result in S6, including:

[0038] S61: The remaining service life prediction model of the structure is ,in is the remaining useful life of the structure, is the corresponding predicted stress level The fatigue life of is the number of cycles that have occurred at a specific stress level, is the maximum stress allowed in the design;

[0039] S62: Use the stress prediction formula in S54 to calculate the total stress of the structure under different conditions ,Will The maximum stress allowed by the design Compare;

[0040] S63: Count the number of cycles the structure has experienced at different stress levels , combined with Corresponding to SN curve calculation Fatigue life ;

[0041] S64: Calculated , , as well as Substitute into the prediction model to obtain the remaining service life of the structure .

[0042] Furthermore, a prefabricated beam string structure dynamic stress analysis system is used to implement any one of the prefabricated beam string structure dynamic stress analysis methods, the prefabricated beam string structure dynamic stress analysis system comprises: a data acquisition and environment monitoring module, a data transmission and security module, a data processing and analysis module, a dynamic stress analysis and health monitoring module, an early warning and decision support module, a user interface and report generation module;

[0043] Data acquisition and environmental monitoring module: Use high-precision strain gauges to monitor the strain changes of the structure, deploy multi-point accelerometers to monitor the vibration characteristics of the structure at different locations, identify the vibration frequency and amplitude, use linear displacement sensors to measure the displacement changes of the structure, deploy temperature sensors to monitor the temperature changes of various parts of the structure, use earth pressure gauges to measure the pressure changes of the soil on the structure, install construction load sensors on construction equipment to monitor the changes in construction loads, and deploy axial force sensors to monitor the changes in the supporting axial forces of the beam string structure supports and connection nodes;

[0044] Data transmission and security module: Combines wired and wireless communication technologies to encrypt data in transit, assigns different priorities to different types of data, adds CRC code to data packets to detect errors during transmission, uses FEC error correction coding technology to automatically repair errors in data transmission at the receiving end, and adopts a role-based access control mechanism to give authorized users access to sensitive data;

[0045] Data processing and analysis module: remove invalid and erroneous data points, calibrate sensor data, synchronize and unify data from different sensors in time, use FFT to analyze vibration signals, extract vibration frequency and amplitude of beam string structure, combine the effect of temperature change on material properties, adjust strain and displacement data, combine nonlinear material properties and geometric nonlinearity, simulate the behavior of structure under complex loads, and use soil mechanics theory to evaluate the force of foundation on structure;

[0046] Dynamic stress analysis and health monitoring module: Combined with the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and support axial force, a stress prediction model is established. By comparing the dynamic stress prediction results with the maximum stress allowed by the design, potential damage areas are identified. Based on the damage identification results, the remaining service life of the structure is predicted;

[0047] Early warning and decision support module: Set early warning thresholds according to structural design standards. Once the monitoring data exceeds the threshold, an alarm is triggered immediately and a notification is sent to relevant personnel. Results based on data analysis are provided to assist engineers and managers in making timely and effective maintenance decisions.

[0048] User Interface and Report Generation Module: Develop a user-friendly interface to display monitoring data and analysis results in a graphical manner, and automatically generate regular monitoring reports summarizing the structural status and recommended measures.

[0049] The beneficial effects of the present invention are: by deploying high-precision strain gauges, multi-point accelerometers, displacement sensors, temperature sensors, earth pressure gauges, construction load sensors and axial force sensors at key parts of the structure, the dynamic response of the structure and environmental influencing factors can be fully monitored, and high-frequency data recording ensures the accuracy of monitoring and helps to capture transient phenomena, such as impact loads during construction;

[0050] Data transmission uses encryption technology and error detection and correction mechanisms to ensure data security and integrity. The role-based access control mechanism ensures data privacy, and only authorized users can access sensitive data.

[0051] Data cleaning, calibration and synchronization improve the quality of data and ensure the accuracy of subsequent analysis. FFT analysis and temperature compensation technology can accurately extract and adjust vibration signals to reflect the actual working state. Finite element analysis software is used to simulate the dynamic response of the structure by combining nonlinear material properties and geometric nonlinearity, which improves the accuracy of prediction.

[0052] The established stress prediction model takes into account multiple factors and can accurately predict the dynamic stress response of the structure. By comparing the predicted stress with the maximum stress allowed by the design, potential damage areas can be discovered in time to prevent major accidents. The prediction of the remaining service life of the structure provides a scientific basis for maintenance and management, and helps to arrange maintenance plans reasonably.

[0053] Setting warning thresholds and immediately triggering alarms when monitoring data exceeds the thresholds helps to take timely measures to avoid accidents. The data analysis results and decision support tools provided help engineers and managers make more accurate judgments. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a flow chart of a dynamic stress analysis method for a prefabricated beam string structure;

[0055] Figure 2 It is a curve diagram of the remaining useful life prediction model of the present invention;

[0056] Figure 3 This is a module diagram of a dynamic stress analysis system for an assembled beam string structure. DETAILED DESCRIPTION

[0057] The present invention is further clearly and completely described below, but the protection scope of the present invention is not limited thereto.

[0058] A method for dynamic stress analysis of an assembled beam string structure, the technical solution adopted is as follows:

[0059] S1: Install high-precision strain gauges to monitor strain changes at key parts of the structure, deploy multi-point accelerometers at different parts of the structure to monitor vibration characteristics, identify vibration frequency and amplitude, use linear displacement sensors to measure displacement changes at different locations of the structure, deploy temperature sensors to monitor temperature changes in various parts of the structure, install earth pressure gauges to measure changes in soil pressure on the structure, install construction load sensors on construction equipment to monitor changes in construction loads, and deploy axial force sensors to monitor changes in the supporting axial forces of the beam string structure supports and connection nodes;

[0060] S2: Combine wired and wireless communication technologies to transmit the collected data, encrypt the data in transmission, assign different priorities to different types of data, add CRC codes to the data packets to detect errors during transmission, and use FEC error correction coding technology to automatically repair errors in data transmission at the receiving end;

[0061] S3: Use a role-based access control mechanism to grant authorized users access to sensitive data;

[0062] S4: Clean the data, remove invalid and erroneous data points, calibrate the sensor data, synchronize and unify the data of different sensors in time, use FFT to analyze the vibration signal, extract the vibration frequency and amplitude of the beam string structure, consider the effect of temperature change on material properties, adjust the strain and displacement data, combine nonlinear material properties and geometric nonlinearity, simulate the behavior of the structure under complex loads, and use soil mechanics theory to evaluate the force of the foundation on the structure;

[0063] S5: Combine the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and support axial force to establish a stress prediction model to predict the dynamic stress response of the structure;

[0064] S6: Identify potential damage areas by comparing the dynamic stress prediction results with the maximum stress allowed by the design, and predict the remaining service life of the structure based on the damage identification results;

[0065] S7: Set warning thresholds according to structural design standards. When monitoring data exceeds the threshold, an alarm is triggered immediately, and notifications are sent to relevant personnel to remind them to take action. Results based on data analysis are provided to assist engineers and managers in making timely and effective maintenance decisions.

[0066] S8: Develop a user-friendly interface to display monitoring data and analysis results in a graphical manner and automatically generate regular monitoring reports summarizing the structural conditions and recommended measures.

[0067] refer to Figure 1 As shown, it is a flow chart of a dynamic stress analysis method of a prefabricated beam string structure.

[0068] Furthermore, the S1 installs a high-precision strain gauge, deploys multi-point accelerometers at different parts of the structure, uses a linear displacement sensor, arranges a temperature sensor, installs an earth pressure gauge, installs a construction load sensor on the construction equipment, and arranges an axial force sensor, including:

[0069] The strain gauge is set with a monitoring frequency of 5Hz and a data recording interval of 1 second. It is installed at the stress-bearing parts and connection nodes of the beam string structure. The accelerometer is set with a monitoring frequency of 50Hz and a data recording interval of 1 second. It is installed at the top, middle and bottom of the beam string structure. The displacement sensor is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 seconds. It is installed at the key support points and free ends of the beam string structure. The temperature sensor is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 minutes. It is installed at various key components and joints of the beam string structure. The soil pressure gauge is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 minutes. It is installed in the soil around the foundation pit. The construction load sensor is set with a monitoring frequency of 5Hz and a data recording interval of 1 second. It is installed on the hook of the crane. The axial force sensor is set with a monitoring frequency of 1Hz and a data recording interval of 1 second. It is installed at the supports and connection nodes of the beam string structure.

[0070] Furthermore, in S2, different priorities are assigned to different types of data, CRC codes are added to data packets to detect errors during transmission, and FEC error correction coding technology is used to automatically repair errors in data transmission at the receiving end, including:

[0071] S21: classify strain data, frequency and amplitude data, and displacement data as high priority data, classify temperature data and soil pressure data as medium priority data, and classify construction load data as low priority data. Control the sending order of data packets at the transmission layer, set queues of different priorities at the data transmission layer, and send high priority data first.

[0072] S22: Select CRC-32 generator polynomial. At the sending end, perform CRC calculation on each data packet and append the CRC value to the end of the data packet. At the receiving end, recalculate the CRC value and compare it with the received CRC value. If the two CRC values ​​do not match, it indicates that an error has occurred in the data packet transmission process.

[0073] S23: At the transmitting end, redundant information is added to each data packet, LDPC coding is selected to encode the data packet, and an additional redundant data packet is generated. At the receiving end, the generated redundant data packet is used to resolve the lost data packet and restore the original data.

[0074] Furthermore, the S3 adopts a role-based access control mechanism, including:

[0075] S31: Data viewing permission is to view real-time data and historical data, data modification permission is to modify data records, including correcting erroneous data, data deletion permission is to delete invalid and outdated data records, data export permission is to export data for further analysis, device management permission is to configure and manage data acquisition devices, user management permission is to create new users, assign roles and permissions, and system configuration permission is to change system configuration, including alarm thresholds;

[0076] S32: Grant all permissions to the project administrator; grant data engineers data viewing permissions, data modification permissions, and equipment management permissions; grant structural engineers data viewing permissions and data export permissions; grant field technicians data viewing permissions and equipment management permissions; grant quality control personnel data viewing permissions and data modification permissions; and grant report writers data viewing permissions and data export permissions.

[0077] Furthermore, the S4 cleans the data, synchronizes and unifies the data of different sensors in time, extracts the vibration frequency and amplitude of the beam string structure, adjusts the strain and displacement data, simulates the behavior of the structure under complex loads, and evaluates the force of the foundation on the structure, including:

[0078] S41: Setting thresholds, identifying and removing data points that are beyond the normal range, and using interpolation to fill in missing and abnormal data points;

[0079] S42: Synchronize the timestamps of all sensors and data acquisition devices, and align the data of different sensors through the timestamps;

[0080] S43: Obtain the modal parameters of the structure, including the natural frequency, damping ratio and vibration mode, use fast Fourier transform (FFT) to analyze the vibration signal, and extract the vibration frequency and amplitude of the beam string structure itself;

[0081] S44: Combined with the influence of temperature change on the elastic modulus and Poisson's ratio of the material, the readings of the strain gauge and the displacement sensor are adjusted according to the temperature change, and the temperature coefficients of the strain gauge and the displacement sensor are obtained, that is, the rate of change of the sensor output when the temperature changes. The data of the strain gauge and the displacement sensor are adjusted according to the temperature coefficient. The adjusted strain value = the original strain value + (strain gauge temperature coefficient × (current temperature − reference temperature)), and the adjusted displacement value = the original displacement value + (displacement sensor temperature coefficient × (current temperature − reference temperature));

[0082] S45: Use finite element software ABAQUS to simulate the dynamic response of the structure under complex loads, consider nonlinear material properties and geometric nonlinearity, perform nonlinear dynamic analysis of the structure, select the time step according to the load characteristics and structural characteristics, and output the dynamic response of the structure under complex loads;

[0083] S46: The data measured by the earth pressure gauge is used in combination with soil mechanics theory and the finite element method to evaluate the pressure distribution of the soil on the structure. The finite element software ABAQUS is used to establish a three-dimensional model including the soil and the structure to analyze the changes in soil pressure over time and construction progress.

[0084] Furthermore, in S5, the stress prediction model is established by combining the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and supporting axial force, including:

[0085] S51: Select features from strain, vibration, displacement, temperature, pressure, construction load data and support axial force, and select strain mean, vibration frequency, amplitude peak, displacement mean, temperature change, pressure mean, construction load mean, and support axial force mean;

[0086] S52: extracting the acceleration change rate from the accelerometer data, extracting the strain gradient from the strain gauge data, extracting the temperature gradient from the temperature sensor data, and extracting the change rate of the construction load from the sensor data on the construction equipment;

[0087] S53: Divide the data set into a training set, a validation set, and a test set, standardize the features extracted in S51 and S52, use the training data set to train the model, use the validation data set to verify the prediction ability of the model, calculate the error between the predicted value and the actual value, and verify the effect of model fusion;

[0088] S54: The stress prediction model is obtained as follows: ,in is the total stress of the structure, is the elastic modulus of the structural material at room temperature, is the temperature coefficient of the structural material, is the temperature change, For strain, is the construction load, is the structural cross-sectional area, is the pressure of soil on the structure, is the vibration effect coefficient related to the structural characteristics, is the amplitude of vibration, is the vibration frequency, is the displacement of the structure, is the displacement gradient, To support the axial force, real-time strain, vibration, displacement, temperature, pressure and construction load data are used as input to obtain the real-time stress value of the structure.

[0089] Furthermore, the remaining service life of the structure is predicted based on the damage identification result in S6, including:

[0090] S61: The remaining service life prediction model of the structure is ,in is the remaining useful life of the structure, is the corresponding predicted stress level The fatigue life of is the number of cycles that have occurred at a specific stress level, is the maximum stress allowed in the design;

[0091] S62: Use the stress prediction formula in S54 to calculate the total stress of the structure under different conditions ,Will The maximum stress allowed by the design Compare;

[0092] S63: Count the number of cycles the structure has experienced at different stress levels , combined with Corresponding to SN curve calculation Fatigue life ;

[0093] S64: Calculated , , as well as Substitute into the prediction model to obtain the remaining service life of the structure .

[0094] refer to Figure 2 The figure shows a curve diagram of the remaining useful life prediction model of the present invention.

[0095] Furthermore, a prefabricated beam string structure dynamic stress analysis system is used to implement any one of the prefabricated beam string structure dynamic stress analysis methods, the prefabricated beam string structure dynamic stress analysis system comprises: a data acquisition and environment monitoring module, a data transmission and security module, a data processing and analysis module, a dynamic stress analysis and health monitoring module, an early warning and decision support module, a user interface and report generation module;

[0096] Data acquisition and environmental monitoring module: Use high-precision strain gauges to monitor the strain changes of the structure, deploy multi-point accelerometers to monitor the vibration characteristics of the structure at different locations, identify the vibration frequency and amplitude, use linear displacement sensors to measure the displacement changes of the structure, deploy temperature sensors to monitor the temperature changes of various parts of the structure, use earth pressure gauges to measure the pressure changes of the soil on the structure, install construction load sensors on construction equipment to monitor the changes in construction loads, and deploy axial force sensors to monitor the changes in the supporting axial forces of the beam string structure supports and connection nodes;

[0097] Data transmission and security module: Combines wired and wireless communication technologies to encrypt data in transit, assigns different priorities to different types of data, adds CRC code to data packets to detect errors during transmission, uses FEC error correction coding technology to automatically repair errors in data transmission at the receiving end, and adopts a role-based access control mechanism to give authorized users access to sensitive data;

[0098] Data processing and analysis module: remove invalid and erroneous data points, calibrate sensor data, synchronize and unify data from different sensors in time, use FFT to analyze vibration signals, extract vibration frequency and amplitude of beam string structure, combine the effect of temperature change on material properties, adjust strain and displacement data, combine nonlinear material properties and geometric nonlinearity, simulate the behavior of structure under complex loads, and use soil mechanics theory to evaluate the force of foundation on structure;

[0099] Dynamic stress analysis and health monitoring module: Combined with the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and support axial force, a stress prediction model is established. By comparing the dynamic stress prediction results with the maximum stress allowed by the design, potential damage areas are identified. Based on the damage identification results, the remaining service life of the structure is predicted;

[0100] Early warning and decision support module: Set early warning thresholds according to structural design standards. Once the monitoring data exceeds the threshold, an alarm is triggered immediately and a notification is sent to relevant personnel. Results based on data analysis are provided to assist engineers and managers in making timely and effective maintenance decisions.

[0101] User Interface and Report Generation Module: Develop a user-friendly interface to display monitoring data and analysis results in a graphical manner, and automatically generate regular monitoring reports summarizing the structural status and recommended measures.

[0102] refer to Figure 3 The figure shows a module diagram of a dynamic stress analysis system for an assembled beam string structure.

[0103] This method proposes a dynamic stress analysis system and method for prefabricated beam string structures. By integrating multiple sensors, comprehensive monitoring of structural strain, vibration, displacement, temperature, soil pressure and construction load is achieved, and data security is ensured through encrypted transmission. A role-based access control mechanism is used to protect sensitive data. During data processing, key vibration features are extracted by cleaning, calibrating and synchronizing data, and the temperature effect is considered. Finite element analysis is used to simulate the structural response, and a stress prediction model is established to identify potential damage areas and predict the remaining service life of the structure, which helps to take maintenance measures in a timely manner, ensure structural safety, and improve the efficiency and accuracy of health management of prefabricated beam string structures.

Claims

1. A method for dynamic stress analysis of an assembled beam string structure, characterized in that: include: S1: Install high-precision strain gauges to monitor strain changes at key parts of the structure, deploy multi-point accelerometers at different parts of the structure to monitor vibration characteristics, identify vibration frequency and amplitude, use linear displacement sensors to measure displacement changes at different locations of the structure, deploy temperature sensors to monitor temperature changes in various parts of the structure, install earth pressure gauges to measure changes in soil pressure on the structure, install construction load sensors on construction equipment to monitor changes in construction loads, and deploy axial force sensors to monitor changes in the supporting axial forces of the beam string structure supports and connection nodes; S2: Combine wired and wireless communication technologies to transmit the collected data, encrypt the data in transmission, assign different priorities to different types of data, add CRC codes to the data packets to detect errors during transmission, and use FEC error correction coding technology to automatically repair errors in data transmission at the receiving end; S3: Use a role-based access control mechanism to grant authorized users access to sensitive data; S4: Clean the data, remove invalid and erroneous data points, calibrate the sensor data, synchronize and unify the data of different sensors in time, use FFT to analyze the vibration signal, extract the vibration frequency and amplitude of the beam string structure, consider the effect of temperature change on material properties, adjust the strain and displacement data, combine nonlinear material properties and geometric nonlinearity, simulate the behavior of the structure under complex loads, and use soil mechanics theory to evaluate the force of the foundation on the structure; S5: Combine the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and support axial force to establish a stress prediction model to predict the dynamic stress response of the structure; S6: Identify potential damage areas by comparing the dynamic stress prediction results with the maximum stress allowed by the design, and predict the remaining service life of the structure based on the damage identification results; S7: Set warning thresholds according to structural design standards. When monitoring data exceeds the threshold, an alarm is triggered immediately, and notifications are sent to relevant personnel to remind them to take action. Results based on data analysis are provided to assist engineers and managers in making timely and effective maintenance decisions. S8: Develop a user-friendly interface to display monitoring data and analysis results in a graphical manner and automatically generate regular monitoring reports summarizing the structural conditions and recommended measures.

2. A method for dynamic stress analysis of an assembled beam string structure according to claim 1, characterized in that: The S1 is equipped with high-precision strain gauges, deploys multi-point accelerometers at different parts of the structure, uses linear displacement sensors, arranges temperature sensors, installs earth pressure gauges, installs construction load sensors on construction equipment, and arranges axial force sensors, including: The strain gauge is set with a monitoring frequency of 5Hz and a data recording interval of 1 second. It is installed at the stress-bearing parts and connection nodes of the beam string structure. The accelerometer is set with a monitoring frequency of 50Hz and a data recording interval of 1 second. It is installed at the top, middle and bottom of the beam string structure. The displacement sensor is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 seconds. It is installed at the key support points and free ends of the beam string structure. The temperature sensor is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 minutes. It is installed at various key components and joints of the beam string structure. The soil pressure gauge is set with a monitoring frequency of 0.5Hz and a data recording interval of 5 minutes. It is installed in the soil around the foundation pit. The construction load sensor is set with a monitoring frequency of 5Hz and a data recording interval of 1 second. It is installed on the hook of the crane. The axial force sensor is set with a monitoring frequency of 1Hz and a data recording interval of 1 second. It is installed at the supports and connection nodes of the beam string structure.

3. A method for dynamic stress analysis of a prefabricated beam string structure according to claim 1, characterized in that: In the S2, different priorities are assigned to different types of data, CRC codes are added to the data packets to detect errors during transmission, and FEC error correction coding technology is used to automatically repair errors in data transmission at the receiving end, including: S21: classify strain data, frequency and amplitude data, and displacement data as high priority data, classify temperature data and soil pressure data as medium priority data, and classify construction load data as low priority data. Control the sending order of data packets at the transmission layer, set queues of different priorities at the data transmission layer, and send high priority data first. S22: Select CRC-32 generator polynomial. At the sending end, perform CRC calculation on each data packet and append the CRC value to the end of the data packet. At the receiving end, recalculate the CRC value and compare it with the received CRC value. If the two CRC values ​​do not match, it indicates that an error has occurred in the data packet transmission process. S23: At the transmitting end, redundant information is added to each data packet, LDPC coding is selected to encode the data packet, and an additional redundant data packet is generated. At the receiving end, the generated redundant data packet is used to resolve the lost data packet and restore the original data.

4. A method for dynamic stress analysis of an assembled beam string structure according to claim 1, characterized in that: The S3 uses a role-based access control mechanism, including: S31: Data viewing permission is to view real-time data and historical data, data modification permission is to modify data records, including correcting erroneous data, data deletion permission is to delete invalid and outdated data records, data export permission is to export data for further analysis, device management permission is to configure and manage data acquisition devices, user management permission is to create new users, assign roles and permissions, and system configuration permission is to change system configuration, including alarm thresholds; S32: Grant all permissions to the project administrator; grant data engineers data viewing permissions, data modification permissions, and equipment management permissions; grant structural engineers data viewing permissions and data export permissions; grant field technicians data viewing permissions and equipment management permissions; grant quality control personnel data viewing permissions and data modification permissions; and grant report writers data viewing permissions and data export permissions.

5. The method for dynamic stress analysis of a prefabricated beam string structure according to claim 1, characterized in that: The S4 cleans the data, synchronizes the data of different sensors in time, extracts the vibration frequency and amplitude of the beam string structure, adjusts the strain and displacement data, simulates the behavior of the structure under complex loads, and evaluates the force of the foundation on the structure, including: S41: Setting thresholds, identifying and removing data points that are beyond the normal range, and using interpolation to fill in missing and abnormal data points; S42: Synchronize the timestamps of all sensors and data acquisition devices, and align the data of different sensors through the timestamps; S43: Obtain the modal parameters of the structure, including the natural frequency, damping ratio and vibration mode, use fast Fourier transform (FFT) to analyze the vibration signal, and extract the vibration frequency and amplitude of the beam string structure itself; S44: Combined with the influence of temperature change on the elastic modulus and Poisson's ratio of the material, the readings of the strain gauge and the displacement sensor are adjusted according to the temperature change, and the temperature coefficients of the strain gauge and the displacement sensor are obtained, that is, the rate of change of the sensor output when the temperature changes. The data of the strain gauge and the displacement sensor are adjusted according to the temperature coefficient. The adjusted strain value = the original strain value + (strain gauge temperature coefficient × (current temperature − reference temperature)), and the adjusted displacement value = the original displacement value + (displacement sensor temperature coefficient × (current temperature − reference temperature)); S45: Use finite element software ABAQUS to simulate the dynamic response of the structure under complex loads, consider nonlinear material properties and geometric nonlinearity, perform nonlinear dynamic analysis of the structure, select the time step according to the load characteristics and structural characteristics, and output the dynamic response of the structure under complex loads; S46: The data measured by the earth pressure gauge is used in combination with soil mechanics theory and the finite element method to evaluate the pressure distribution of the soil on the structure. The finite element software ABAQUS is used to establish a three-dimensional model including the soil and the structure to analyze the changes in soil pressure over time and construction progress.

6. A method for dynamic stress analysis of a prefabricated beam string structure according to claim 1, characterized in that: In S5, the stress prediction model is established by combining the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and supporting axial force, including: S51: Select features from strain, vibration, displacement, temperature, pressure, construction load data and support axial force, and select strain mean, vibration frequency, amplitude peak, displacement mean, temperature change, pressure mean, construction load mean, and support axial force mean; S52: extracting the acceleration change rate from the accelerometer data, extracting the strain gradient from the strain gauge data, extracting the temperature gradient from the temperature sensor data, and extracting the change rate of the construction load from the sensor data on the construction equipment; S53: Divide the data set into a training set, a validation set, and a test set, standardize the features extracted in S51 and S52, use the training data set to train the model, use the validation data set to verify the prediction ability of the model, calculate the error between the predicted value and the actual value, and verify the effect of model fusion; S54: The stress prediction model is obtained as follows: ,in is the total stress of the structure, is the elastic modulus of the structural material at room temperature, is the temperature coefficient of the structural material, is the temperature change, For strain, is the construction load, is the structural cross-sectional area, is the pressure of soil on the structure, is the vibration effect coefficient related to the structural characteristics, is the amplitude of vibration, is the vibration frequency, is the displacement of the structure, is the displacement gradient, To support the axial force, real-time strain, vibration, displacement, temperature, pressure and construction load data are used as input to obtain the real-time stress value of the structure.

7. A method for dynamic stress analysis of a prefabricated beam string structure according to claim 1, characterized in that: In S6, based on the damage identification result, the remaining service life of the structure is predicted, including: S61: The remaining service life prediction model of the structure is ,in is the remaining useful life of the structure, is the corresponding predicted stress level The fatigue life of is the number of cycles that have occurred at a specific stress level, is the maximum stress allowed in the design; S62: Use the stress prediction formula in S54 to calculate the total stress of the structure under different conditions ,Will The maximum stress allowed by the design Compare; S63: Count the number of cycles the structure has experienced at different stress levels , combined with Corresponding to SN curve calculation Fatigue life ; S64: Calculated , , as well as Substitute into the prediction model to obtain the remaining service life of the structure .

8. A dynamic stress analysis system for assembled beam string structures, characterized in that: A method for dynamic stress analysis of a prefabricated beam string structure is used to implement any one of the above, wherein the prefabricated beam string structure dynamic stress analysis system comprises: a data acquisition and environment monitoring module, a data transmission and security module, a data processing and analysis module, a dynamic stress analysis and health monitoring module, an early warning and decision support module, and a user interface and report generation module; Data acquisition and environmental monitoring module: Use high-precision strain gauges to monitor the strain changes of the structure, deploy multi-point accelerometers to monitor the vibration characteristics of the structure at different locations, identify the vibration frequency and amplitude, use linear displacement sensors to measure the displacement changes of the structure, deploy temperature sensors to monitor the temperature changes of various parts of the structure, use earth pressure gauges to measure the pressure changes of the soil on the structure, install construction load sensors on construction equipment to monitor the changes in construction loads, and deploy axial force sensors to monitor the changes in the supporting axial forces of the beam string structure supports and connection nodes; Data transmission and security module: Combines wired and wireless communication technologies to encrypt data in transit, assigns different priorities to different types of data, adds CRC code to data packets to detect errors during transmission, uses FEC error correction coding technology to automatically repair errors in data transmission at the receiving end, and adopts a role-based access control mechanism to give authorized users access to sensitive data; Data processing and analysis module: remove invalid and erroneous data points, calibrate sensor data, synchronize and unify data from different sensors in time, use FFT to analyze vibration signals, extract vibration frequency and amplitude of beam string structure, combine the effect of temperature change on material properties, adjust strain and displacement data, combine nonlinear material properties and geometric nonlinearity, simulate the behavior of structure under complex loads, and use soil mechanics theory to evaluate the force of foundation on structure; Dynamic stress analysis and health monitoring module: Combined with the data of strain change, vibration frequency and amplitude, displacement, temperature, pressure, construction load and support axial force, a stress prediction model is established. By comparing the dynamic stress prediction results with the maximum stress allowed by the design, potential damage areas are identified. Based on the damage identification results, the remaining service life of the structure is predicted; Early warning and decision support module: Set early warning thresholds according to structural design standards. Once the monitoring data exceeds the threshold, an alarm is triggered immediately and a notification is sent to relevant personnel. Results based on data analysis are provided to assist engineers and managers in making timely and effective maintenance decisions. User Interface and Report Generation Module: Develop a user-friendly interface to display monitoring data and analysis results in a graphical manner, and automatically generate regular monitoring reports summarizing the structural status and recommended measures.

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